Ellis was supposed to keep within one millimeter, one twenty-fifth of an inch, of the assigned track. He deviated half a millimeter.

"50 TRACK ERROR," warned the computer. Ross said, "You're slipping off."

The electrode array stopped in its path. Ellis glanced up at the screens. "Too high on beta plane?"

"Wide on gamma."

"Okay."

After a moment, the electrodes continued along the path.

"40 TRACK ERROR," the computer flashed. It rotated its brain image slowly, bringing up an anterolateral view. "20 TRACK

ERROR," it said.

"You're correcting nicely," Ross said.

Ellis hummed along with the Bach and nodded.

"ZERO TRACK ERROR," the computer indicated, and swung the brain view around to a full lateral. The second screen showed a full frontal view. After a few moments, the screen blinked

"APPROACHING TARGET." Ross conveyed the message.

Seconds later, the flashing word "STRIKE."

"You're on," Ross said.

Ellis stepped back and folded his hands across his chest.

"Let's have a coordinate check," he said. The elapsed-time clock showed that twenty-seven minutes had passed in the operation.

The programmer flicked the console buttons rapidly. On the TV screens, the placement of the electrode was simulated by the computer. The simulation ended, like the actual placement, with the word "STRIKE."

"Now match it," Ellis said.

The computer held its simulation on one screen and matched it to the X-ray image of the patient. The overlap was perfect; the computer reported "MATCHED WITHIN ESTABLISHED LIMITS."

"That's it," Ellis said. He screwed on the little plastic button cap which held the electrodes tightly against the skull. Then he applied dental cement to fix it. He untangled the twenty fine wire leads that came off the electrode array and pushed them to one side.

"We can do the next one now," he said.

At the end of the second placement, a thin, arcing cut was made with a knife along the scalp. To avoid important superficial vessels and nerves, the cut ran from the electrode entry points down the side of the ear to the base of the neck. There it deviated to the right shoulder. Using blunt dissection, Ellis opened a small pocket beneath the skin of the right lateral chest, near the armpit.

"Have we got the charging unit?" he asked.

The charger was brought to him. It was smaller than a pack of cigarettes, and contained thirty-seven grams of the radioactive isotope plutonium-239 oxide. The radiation produced heat, which was converted directly by a thermionic unit to electric power. A Kenbeck solid-state DC/DC circuit transformed the output to the necessary voltage.

Ellis plugged the charger into the test pack and did a last-minute check of its power before implantation. As he held it in his hand, he said, "It's cold. I can't get used to that." Ross knew layers of vacuum-foil insulation kept the exterior cool and that inside the packet the radiation capsule was producing heat at 500 degrees Fahrenheit - hot enough to cook a roast.

He checked radiation to be sure there would be no leakage. The meters all read in the low-normal range. There was a certain amount of leakage, naturally, but it was no more than that produced by a commercial color television set.

Finally he called for the dog tag. Benson would have to wear this dog tag for as long as he had the atomic charging unit in his body. The tag warned that the person had an atomic pacemaker, and gave a telephone number. Ross knew that the number was a listing which played a recorded message twenty-four hours a day. The recording gave detailed technical information about the charging unit, and warned that bullet wounds, automobile accidents, fires, and other damage could release the plutonium, which was a powerful alpha-particle emitter. It gave special instructions to physicians, coroners, and morticians, and warned particularly against cremation of the body, unless the charger was first removed.

Ellis inserted the charging unit into the small subdermal pocket he had made in the chest wall. He sewed tissue layers around it to fix it in place. Then he turned his attention to the postage-stamp-sized electronic computer.

Ross looked up at the viewing gallery and saw the wizard twins, Gerhard and Richards, watching intently. Ellis checked the packet under the magnifying glass, then gave it to a scrubbed technician, who hooked the little computer into the main hospital computer.

To Ross, the computer was the most remarkable part of the entire system. Since she had joined the NPS three years before, she had seen the computer shrink from a prototype as large as a briefcase to the present tiny model, which looked small in the palm of a hand yet contained all the elements of the original bulky unit.

This tiny size made subdermal implantation possible. The patient was free to move about, take showers, do anything he wanted. Much better than the old units, where the charger was clipped to a patient's belt and wires dangled down all over.

She looked at the computer screens which flashed

"OPERATIVE MONITORS INTERRUPTED FOR ELECTRONICS CHECK." On one screen, a blown-up circuit diagram appeared. The computer checked each pathway and component independently. It took four-millionths of a second for each check; the entire process was completed in two seconds. The computer flashed

"ELECTRONIC CHECK NEGATIVE." A moment later, brain views reappeared. The computer had gone back to monitoring the operation.

"Well," Ellis said, "let's hook him up." He painstakingly attached the forty fine wire leads from the two electrode arrays to the plastic unit. Then he fitted the wires down along the neck, tucked the plastic under the skin, and called for sutures. The elapsed-time clock read one hour and twelve minutes.

2

Morris wheeled Benson into the recovery room, a long, low-ceilinged room where patients were brought immediately after operation. The NPS had a special section of the rec room, as did cardiac patients and burns patients. But the NPS section, with its cluster of electronic equipment, had never been used before. Benson was the first case.

Benson looked pale but otherwise fine; his head and neck were heavily bandaged. Morris supervised his transfer from the rolling stretcher to the permanent bed. Across the room, Ellis was telephoning in his operative note. If you dialed extension 1104, you got a transcribing machine. The dictated message would later be typed up by a secretary and inserted in Benson's record.

Ellis's voice droned on in the background. "... centimeter incisions were made over the right temporal region, and 2-millimeter burr holes drilled with a K-7 drill. Implantation of Briggs electrodes carried out with computer assistance on the LIMBIC Program. Honey, that's spelled in capital letter, L-I-M-B-I-C. Program. X-ray placement of electrodes determined with computer review as within established limits. Electrodes sealed with Tyler fivation caps and seven-oh-grade dental sealer. Transmission wires- "

"What do you want on him?" the rec-room nurse asked.

"Vital signs Q five minutes for the first hour, Q fifteen for the second, Q thirty for the third, hourly thereafter. If he's stable, you can move him up to the floor in six hours."

The nurse nodded, making notes. Morris sat down by the bedside to write a short operative note:

Short operative note on Harold F. Benson

Pre-op dx: psychomotor (temporal lobe) epilepsy

Post-op dx: same

Procedure: implantation of twin Briggs electrode arrays into right temporal lobe with subdermal placing of computer and plutonium charging unit.

Pre-op meds:

phenobarbital 500 mg

one hr. prior to

atropine 60 mg procedure

Anaesthesia: lidocaine (1/1000) epinephrine locally

Estimated blood loss: 250 cc

Fluid replacement: 200 cc D5/W Operative duration: 1 hr. 12 min. Post-op condition: good

As he finished the note, he heard Ross say to the nurse,

"Start him on phenobarb as soon as he's awake." She sounded angry.

He looked up at her. "Something the matter?"

"No," she said.

"You seem angry."

"Are you picking a fight with me?"

"No," he said, "of course- "

"Just make sure he gets his phenobarb. We want to keep him sedated until we can interface him."

And she stormed out of the room. Morris watched her go, then glanced over at Ellis, who was still dictating but had been watching. Ellis shrugged.

"What's the matter with her?" the nurse asked.

"Probably just tired," Morris said. He adjusted the monitoring equipment on the shelf above Benson's head. He turned it on and waited until it warmed up. Then he placed the temporary induction unit around Benson's taped shoulder.

During the operation, all the wires had been hooked up, but they were not working now. Before that happened, Benson had to be "interfaced." This meant determining which of the forty electrodes would stop an epileptic seizure, and locking in the appropriate switches on the subdermal computer.

Because the computer was under the skin, the locking in would be accomplished by an induction unit, which worked through the skin. But the interfacing couldn't be done until tomorrow.

Meanwhile, the equipment monitored Benson's brainwave activity. The screens above the bed glowed a bright green, and showed the white tracing of his EEG. The pattern was normal for alpha rhythms slowing from sedation.

Benson opened his eyes and looked at Morris.

"How do you feel?" he asked.

"Sleepy," he said. "Is it beginning soon?"

"It's over," Morris said.

Benson nodded, not at all surprised, and closed his eyes.

A rad-lab technician came in and checked for leakage from the plutonium with a Geiger counter. There was none. Morris slipped the dog tag around Benson's neck. The nurse picked it up curiously, read it, and frowned.

Ellis came over. "Time for breakfast?"

"Yes," Morris said. "Time for breakfast."

They left the room together.

Chapter 6

3

The trouble was he didn't really like the sound of his voice. His voice was rough and grating, and his enunciation was poor. McPherson preferred to see the words in his mind, as if they had been written. He pressed the microphone button on the dictation machine. "Roman numeral three. Philosophical Implications."

III. Philosophical Implications.

He paused and looked around his office. The large model of the brain sat at the corner of his desk. Shelves of journals along one wall. And the TV monitor. On the screen now he was watching the playback of the morning's operation. The sound was turned off, the milky images silent. Ellis was drilling holes in Benson's head. McPherson watched and began to dictate.

This procedure represents the first direct link between a human brain and a computer. The link is permanent. Now of course, any man sitting at a computer console and interacting with the computer by pressing buttons can be said to be linked.

Too stuffy, he thought. He ran the tape back and made changes. Now, a man sitting at a computer console and interacting with the computer by pressing buttons is linked to the computer. But that link is not direct. And the link is not permanent. Therefore, this operative procedure represents something rather different. How is one to think about it?

A good question, he thought. He stared at the TV image of the operation, then continued.

One might think of the computer in this case as a prosthetic device. Just as a man who has his arm amputated can receive a mechanical equivalent of the lost arm, so a brain-damaged man can receive a mechanical aid to overcome the effects of brain damage. This is a comfortable way to think about the operation. It makes the computer into a high-class wooden leg. Yet the implications go much further than that.

He paused to look at the screen. Somebody at the main tape station had changed reels. He was no longer seeing the operation, but a psychiatric interview with Benson before the surgery. Benson was excited, smoking a cigarette, making stabbing gestures with the lighted tip as he spoke.

Curious, McPherson turned the sound up slightly. "... know what they're doing. The machines are everywhere. They used to be the servants of man, but now they're taking over. Subtly, subtly taking over."

Ellis stuck his head into the office, saw the TV screen, and smiled. "Looking at the 'before' pictures?"

"Trying to get a little work done," McPherson said, and pointed to the dictation machine.

Ellis nodded, ducked out, closing the door behind him.

Benson was saying, "... know I'm a traitor to the human race, because I'm helping to make machines more intelligent. That's my job, programming artificial intelligence, and- "

McPherson turned the sound down until it was almost inaudible. Then he went back to his dictation.

In thinking about computer hardware, we distinguish between central and peripheral equipment. That is, the main computer is considered central even though, in human terms, it may be located in some out-of-the-way place - like the basement of a building, for example. The computer's read-out equipment, display consoles, and so on, are peripheral. They are located at the edges of the computer system, on different floors of the building.

He looked at the TV screen. Benson was particularly excited. He turned up the sound and heard, "... getting more intelligent. First steam engines, then automobiles, and airplanes, then adding machines. Now computers, feedback loops- "

McPherson turned the sound off.

For the human brain, the analogy is a central brain and peripheral terminals, such as mouth, arms, and legs. They carry out the instructions - the output - of the brain. By and large, we judge the workings of the brain by the activity of these peripheral functions. We notice what a person says, and how he acts, and from that deduce how his brain works. This idea is familiar to everyone.

He looked at Benson on the TV screen. What would Benson say? Would he agree or disagree? But then did it matter?

Now, however, in this operation we have created a man with not one brain but two. He has his biological brain, which is damaged, and he has a new computer brain, which is designed to correct the damage. This new brain is intended to control the biological brain. Therefore a new situation arises. The patient's biological brain is the peripheral terminal - the only peripheral terminal - for the new computer. In one area, the new computer brain has total control. And therefore the patient's biological brain, and indeed his whole body, has become a terminal for the new computer. We have created a man who is one single, large, complex computer terminal. The patient is a read-out device for the new computer, and he is as helpless to control the read-out as a TV screen is helpless to control the information presented on it.